See the building’s energy class – new feature in BIM Energy Renovation
A new feature in BIM Energy Renovation is the presentation of the building’s energy class. The building’s primary energy number is calculated and compared against the Swedish building requirements in BBR 29. This allows for studying how the building’s energy class changes with different renovation measures.
A building’s energy class is relevant in the EU’s directive on the energy performance of buildings (EPBD) to assess to what extent the building needs renovation to achieve a zero-emission building level.
One part of a building’s energy certificate is to specify the building’s energy performance. From January 1, 2019, a building’s energy performance in Sweden is indicated as a primary energy number (EPpet, see formula below). The primary energy number is calculated based on the summary of the building’s energy consumption for heating, cooling, hot tap water, and building operational electricity, where each energy carrier (electricity, district heating, district cooling, biofuels, fossil fuels) has a weight factor (VF). Additionally, the building’s location in the country is taken into account through the geographical adjustment factor (Fgeo)
These factors allow for comparing the energy performance between different buildings regardless of energy sources and geographic location. This summation is then divided by the heated floor area of the building (Atemp) to obtain the building’s energy performance [kWh/m2].
A building’s primary energy number is calculated with this equation:
There are 7 energy classes (A-G) for properties, based on the requirements for energy performance applicable to new buildings constructed today.
Energy class A represents low energy consumption and G represents high consumption. A building that meets the requirements set for a newly built house today receives class C or better.
The requirements for energy performance in a new building vary between different building types (single-family houses, multi-family houses, or commercial premises) and are currently specified in BBR 29 (March 2024).